Protective coating for surfaces of silver and mirror fabrication

ABSTRACT

THE PRESENT INVENTION INCLUDES A PROTECTIVE COATING FOR HIGHLY REFLECTIVE SURFACES OF SILVER OR SILVER ALLOYS AND IS ACCOMPLISHED BY APPLYING A TRANSPARENT LAYER OF ALUMINUM OXIDE TO THE SURFACE OF SILVER TO BE PROTECTED AND THEREAFTER APPLYING A TRANSPARENT LAYER OF QUARTZ (SILICON DIOXIDE) OVER THE LAYER OF ALUMINUM OXIDE. IN ADDITION THE SILVER IS SECURED ON ITS NON-REFLECTING SURFACE TO A LAYER OF CHROMIUM-NICKEL ALLOY. THE ENTIRE FOUR LAYER PACKAGE CAN BE READILY SECURED TO A SILICEOUS SUBSTRATE, TO A PLASTIC SUBSTRATE OR TO A HIGHLY POLISHED METAL SUBSTRATE AND WILL   WITHSTAND THE NORMAL TESTING PROGRAM. FURTHER IF THERE IS A LAYER OF ALUMINUM BETWEEN THE CHROMIUM NICKEL ALLOY AND CERTAIN SUBSTRATES THE ENTIRE PACKAGE CAN BE READILY PEELED OFF THESE SUBSTRATES AS IS SOMETIMES NECESSARY WHEN PRODUCING LARGE MIRRORS.

Augo 29, 72 H. N. ADAMS 3,687,713

PROTECTIVE COATING POR SURFACES OP SILVER AND MIRROR FABRICATION Fi19d arch 15' 1971 2 sheetssheet ZNVENTOR} Horve N. Adoms ATTORNEY( 9, 1972 H{ N. ADAMS 3,687,7l3

PROTECTIVE COATING POR SURFACES OF SILVER AND MIRROR FABRICATION INVENTOR. Horvey N Ad0ms ATTORNEY Substantiauy Silver, a layer Of aluminum oxide secured said outer Suface, and a layer of silico11 dioxide se cured to Said layer 0f aluIfinun1 0xide z. 1 T()tective coating nleans on a Substrate according t0 clai111 1 Wherein Said outer surface iS SubStantia1y pure Silver.

3' Protective coating Ineans on a Substrate according to claim l Wherein said outer surface is a SHver metal auoy selected from the group: nickelcht0miumiron-snver chron1iunnicke-Silver, and chron1iun-silver.

4. l,rotective coating n]eans 011 a substrateaccording to claim 1 Wherein Sad Substrate comprises a layer of Inetal InateriaI, a layer of chr0IniuIn-Iickel alloy Secured to Said layer of metal Ilaterial, and a layer of nlateria of Substantially Silver Secured t0 Said ayer of C11T0Iniunnickel anoy.

s Pr0tective coating nleans on a Substrate according to claim l wherein Said substrate comprise8 a layel of a highly p01ished 11]etal, a layer of chr()1T1i[ll]1-1ickel alloy secured to Said layer of highly polished metal, and a layer of n1ateria of Substantially silver Secured to Said layer of chromiumnicke] alloy Protective coating means on a Substrate according to claim 1 Wherein Said Substrate c0mprises a layer of plastic materia, a layer of chr0nliumnickel alloy Secured to said layer of plastic, and a layer of Inaterial of sub- Stantially Silver Secured to Said layeT of chTotniun1-11icke1( 7. Protective coating n1eans on a subSrate according to clailn 1 Wherein said substrate consists of a decoTative silver item 8. PTotective coating 1eanS On a Substrate according to clain1 1 Wheein said Substrate c0mprises a layer of Silice0us n1aterial, a layer of chro!niun!nicke1 alloy Secured to said layer of siliceous lllaterial, and a layer of material of substantiany Silver secured to Said layer of chronliun1nickel anoy 9. PTotective coating Ilealls 0Il a substrate according to claim 8 Whetein said layer of Inaterial containing silver iS a layer of substantiany pure Silvel 10. PTOtective coatillg*Tleal18 ()l1 a Substrate according t0 claim l wherein Said layer of alumium oxide has a thickness which is equal to 0f a partculal Wavelength, Said Wavelength being a Wavelength of energy i the light spectrum Whereat the reecti0n of light is to be enhanced and vvhe[ein said layer of siicon dioxide ha Sub8tantially the Sa[le thick11ess as Said layer of alu[1i num oxide 11] Pr0tective c()ai]1gneans on a substrate according t() claim 10 Wherein said articular Wavelength is be tween 4000 and 7000 angstroms.

l2r. PTotective coating Ineans on a Substrate accordil1g t0 claim 1 vvherein said substrate cohprises v3' layer o Siliceous naterial, a layer of a1ulT1inunl Secured to said layer of Siliceous nlaterial, a layer of ch0miun1-nicke1 alloy Secured t0 Said layer of aluminum, and a ayr of Inaterial of SubStantally'silver Secued to Said layef of chron1iun1nickel a]10y.

13. 1 Totective coating n1eans on a substrate according to claim lz Wherein said layer of aluminum iS a T0Xi mately 200 angstrons in thickness 3,601,47l 8/197l Seddon 117 3S v ALFRED L. LEAVITT, Primaf Examiner C K. VVEIFFENBACH, Assistant Examiner 

